Awareness of the need for biodiversity conservation is now universally accepted, but most often recent conservation activities have focused on wild species. Crop species and the diversity between and within them has significant socioeconomic as well as heritage value. The bulk of genetic diversity in domesticated species is located in traditional varieties maintained by traditional farming systems. These traditional varieties, commonly referred to as landraces, are severely threatened by genetic extinction primarily due to their replacement by modern genetically uniform varieties. The conservation of landrace diversity has been hindered in part by the lack of an accepted definition to define the entity universally recognized as landraces. Without a definition it would be impossible to prepare an inventory and without an inventory changes in landrace constituency could not be recognized over time. Therefore, based on a literature review, workshop discussion and interviews with key informants, common characteristics of landraces were identified, such as: historical origin, high genetic diversity, local genetic adaptation, recognizable identity, lack of formal genetic improvement, and whether associated with traditional farming systems. However, although these characteristics are commonly present they are not always all present for any individual landrace; several crop-specific exceptions were noted relating to crop propagation method (sexual or asexual), breeding system (self-fertilized or cross-fertilized species), length of formal crop improvement, seed management (selection or random propagation) and use. This paper discusses the characteristics that generally constitute a landrace, reviews the exceptions to these characteristics and provides a working definition of a landrace. The working definition proposed is as follows: ‘a landrace is a dynamic population(s) of a cultivated plant that has historical origin, distinct identity and lacks formal crop improvement, as well as often being genetically diverse, locally adapted and associated with traditional farming systems’.

Frost damage was evaluated in 1-year-old olive trees in the cultivars ‘Arbequina’, ‘Cornicabra’, ‘Empeltre’, ‘Frantoio’, ‘Hojiblanca’, ‘Manzanilla Cacereña’, ‘Nevadillo de Jaén’, ‘Picual’, ‘Picudo’ and ‘Verdial de Badajoz’ in Madrid, Spain. Temperatures fell to −6.5 and −10.5°C on 11 November and 16 December 2001, respectively. In May frost damage was visually assessed. The olive trees were pruned to the ground and dry matter was quantified in shoots and leaves with and without signs of frost damage. In August resprouting was visually evaluated. Visual assessment overestimated frost damage compared to the quantitative evaluation. Leaves had a lower resistance to frost than shoots. Shoot frost resistance was linearly correlated to the cultivar's resprouting capacity. Significant differences in frost resistance were found between cultivars. ‘Cornicabra’ and ‘Arbequina’ had a low percentage of frost-damaged shoots and a high resprouting capacity after frost. The cultivars which were the least resistant to frost were ‘Empeltre’, ‘Frantoio’ and ‘Hojiblanca’. These cultivars had a high percentage of frost-damaged shoots and almost no resprouting capacity. ‘Picual’, ‘Picudo’, ‘Verdial de Badajoz’, ‘Manzanilla Cacereña’ and ‘Nevadillo de Jaén’ had an intermediate frost resistance.

Fifty lines of Medicago truncatula, derived from ecotypes or cultivars of diverse geographical origin, were grown under uniform conditions, and variation in seed protein composition and quantity was investigated. One-dimensional electrophoretic profiles revealed 46 major seed polypeptides, of which 26 were polymorphic within the collection. The vicilin/convicilin (7S) and the legumin (11S) type proteins were identified by immunoblotting using antibodies raised against the homologous pea proteins. The polymorphism for the major seed protein classes allowed the clustering of the genotypes into four groups. There was no evidence of clustering according to geographical origin of the lines. However, all lines not belonging to either M. truncatula ssp. truncatula or ssp. longispina were clustered in a single group, demonstrating the value of seed protein profiles in delimiting species boundaries. The Jemalong line group was differentiated early in the dendrogram, and thus represents an ancient clade in the seed diversity of M. truncatula. Within-accession variation was investigated for one-dimensional seed profiles, with additional lines obtained from the same ecotypes. As expected for an autogamous species, within-accession variation was low. Seed protein content was highly variable among the 50 lines examined. Lines contrasting for qualitative traits and seed protein content were identified to allow for the genetic determination of these characters.

Dendrobium Sw., a member of the family Orchidaceae, includes approximately 1100 species distributed in different parts of the world. In China, the genus is represented by 76 species and two varieties, of which D. loddigesii, D. fimbriatum, D. chrysanthum, D. officinale (=D. candidum) and D. nobile are listed in the Chinese Pharmacopoeia as the source material for Herba Dendrobii (Shihu). Because of increased demand and high price, Herba Dendrobii is often adulterated in the trade by other related species. Many Dendrobium species are over-collected from the wild and are listed under endangered taxa in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Therefore, a reliable authentication method is needed to regulate the trade and help conserve the species from unscrupulous collections. This review describes the present status of using medicinal Dendrobium in China, current approaches to authenticate medicinal Dendrobium plants and Herba Dendrobii, and the efforts under way towards the development of DNA microarrays to facilitate differentiation/identification of genuine material in complex Chinese medicinal formulations.

We successfully generated clear amplified fragment length polymorphism (AFLP) profiles of Anemone coronaria using only a single restriction enzyme (EcoR I). Four primer combinations generated 571 bands in 37 anemone accessions with an average 142.75 bands per primer combination. Polymorphism among the 37 samples was very high (98.15%). This high polymorphism showed that the one-enzyme AFLP method is effective for the assessment of genetic diversity as well as cultivar differentiation of anemone. We observed 26 bands which differentiated between fingerprints derived from leaf and corm DNA of eight plant individuals. However, the low percentage of such bands showed that anemone corms can also be used to evaluate anemone germplasm using AFLP markers.

This paper examines the fate of alleles and changes of genetic diversity in old (ca 1930s) versus more modern (ca 1990s) UK bread wheat varieties using 14 mapped DNA microsatellite (simple sequence repeat, SSR) loci and morphological markers. The allelic constitution of varieties belonging to three time periods (early, intermediate, late) was determined. While at certain loci one or more SSR alleles were gained between early and late periods, at others the allelic representation remained constant, although a shift in allelic frequencies could sometimes be detected. No locus showed a clear, net loss in the total number of alleles over the time period. In a further group of loci, there was neither clear gain nor loss, but rather a dynamic flux of alleles. A comparison of the allelic constitution of the UK variety set with a larger genetic pool (non-UK varieties) showed that some loci were rather similar in allelic constitution, while others possessed additional diversity. Certain SSR alleles appeared to be associated with old or modern varieties, possibly indicating associations with chromosome regions under selection pressure. The same exercise was conducted on the basis of 14 of the morphological characteristics recorded in the course of distinctness, uniformity and stability testing of varieties. Overall, this analysis generated a similar picture of changes in diversity to that obtained from the microsatellite data.

Hydro-distilled essential oils from fruits, aerial parts (without fruits) and roots of Pimpinellaspecies native to Turkey and their phylogenetic relationships to one another were examined. Phytochemical investigation of the essential oils of 19 species resulted in isolation of 16 phenylpropanoids, four sesquiterpenes and two azulene-type norsesquiterpenes. The structures of the isolated compounds were determined primarily from 1D- and 2D-NMR experiments as well as liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry. Phylogenetic relationships among 26 species were evaluated using ITS 1, ITS 4 nuclear rDNA and psbA-trnH cpDNA sequences. In this study, significance and occurrence of phenylpropanoids, azulenes and geijerenes are discussed from a phylogenetic, chemical and biosynthetic perspective. The distribution of different classes of compounds and their putative associations with one another as per current knowledge of their biosynthetic pathways indicates that this information, in conjunction with the phylogeny, could provide valuable information regarding the presence and perhaps evolution of the different classes of compounds. Analysis of the phenylpropanoid components indicates that (E)-anethole is an obligatory intermediate of this pathway. The various Pimpinellaspecies differ primarily in their ability to acylate anethole, suggesting that while the pathway leading to anethole is common to this genus, species differ in their enzymatic machinery leading to acylate. The relationship between azulenes and geijerenes is not as intuitive, but all Pimpinellaspecies analysed in this study have the biochemical machinery required to synthesize these chemical classes.

Traditional vegetables in Tanzania have been underutilized by farmers and neglected by research and development programmes. In the framework of the project ‘Promotion of Neglected Indigenous Vegetable Crops for Nutritional Health in Eastern and Southern Africa’ led by the World Vegetable Center (AVRDC) and partners, focus group meetings were conducted in 10–12 villages in each of four districts of north-east Tanzania, which differed in ethnicity as well as in altitude, climate and soil conditions. Farmers named 10–34 different traditional vegetables per village, summing up to an overall of 102 in all four districts, about half of which were only identified by local names. The number of wild traditional vegetables used was always greater than the number of cultivated traditional types, with ratios of wild to cultivated vegetables ranging from 11:9 in an urban highland district to 59:11 in a rural coastal district. Some wild traditional vegetables were found to be threatened with genetic erosion due to changes in land use and eating habits. The degree of urbanization and the availability of infrastructure contributed more strongly to genetic erosion as compared to climatic conditions. Farmers' training encouraged exotic vegetable cultivation and reduced traditional vegetable diversity. At the same time, indigenous knowledge on how and where to collect, cultivate and prepare traditional vegetables was disappearing.

Polyploidization is often accompanied by increased cell size and conspicuous changes in secondary metabolism. Where vegetative plant organs are the source of secondary metabolites, as is the case with most medicinal plants, ploidy manipulations such as direct chromosome doubling or allopolyploidization provide a rapid means to realize enhanced production of phyto-pharmaceuticals. Supported with prospective examples, this article illustrates the potential of genomic and ploidy manipulation to enhance the resourcing of pharmaceuticals of plant origin and suggests some appropriate strategies for optimum utilization.

Numerous factors influence the chemical quality of medicinal plants from crop establishment to extraction of raw material. The most important ones are described using the example of Hypericum perforatum. Optimization of these factors contributes to the objective of producing a high-quality drug, and a method consisting of three scientific approaches (technological, agronomical, plant breeding) is presented. All data concerning the plant (biology, physiology and environmental impacts) and the active components and by-products (pathway, localization and stability) are useful to adapt and to develop management sequences. Although plant breeding appears to be the principal way of improvement, and gives good results in terms of resistance to pathogens, active component content and yield; the agronomical and the technological approaches are also very important. The technological approach after harvesting is especially important to avoid degradation of the active components and to induce, in some cases, the transformation of by-products to those molecules sought. This integrated method (plant breeding and agronomical and chemical approaches) requires research on different levels of organization from molecule to field, and includes all processing systems from farmers to chemists.

Dallisgrass (Paspalum dilatatum Poir.) is an important pasture grass on moist fertile sites in warm climates, however, it is limited in use by periodic low seed quality and resulting erratic availability and establishment difficulties. Due to apomictic reproduction, common pentaploid dallisgrass has not been responsive to traditional plant improvement approaches. Recent research has shown potential for some improvement in forage production and plant persistence with apomictic hexaploid varieties of dallisgrass. Tissue-culture regeneration has been reported to produce somaclonal variation in seed germination of common pentaploid dallisgrass and has recently resulted in availability of potentially useful regenerants of hexaploid dallisgrass. Seed of selected plants from both field and greenhouse environments was evaluated in replicated germination trials to determine whether hexaploid tissue-culture regenerants responded similarly to regenerants from common dallisgrass and to determine whether regenerants expressing potential agronomic usefulness as indicated by preliminary observations differed in germination. The eight germination trials included 299 regenerants with 57 of these being duplicate entries among trials. Germination did not differ among sources of regenerants. Within sources germination differed among regenerants with a few individuals exceeding germination percentage of parent lines in one evaluation of greenhouse-produced seed. Individual regenerants with agronomic potential and high percentage seed germination were identified. The results demonstrate that tissue-culture regeneration can be used to produce improved germination in agronomically useful genotypes of apomictic dallisgrass and suggest that such potential may exist for other recalcitrant plant species.

Well-defined descriptors are an indispensable tool for management, maintenance and utilization of plant genetic resources. The International Plant Genetic Resources Institute (IPGRI), the International Union for the Protection of New Varieties of Plants (UPOV) and national authorities have published descriptor lists for a great variety of agricultural and horticultural crops, but only for a few species belonging to the group of medicinal and aromatic plants (MAP). Forty years of experiences with the use of descriptors in MAP mainly in the field of breeding research are communicated to support forthcoming efforts in elaborating new descriptors lists. The deliberations focus on some specifics of these minor crops, classifying the descriptors to the following groups: object, experimental data, sample specification, characteristics—growth, development, flower and reproduction biology, cytological traits, molecular traits, biotic and abiotic stress susceptibility, yield, quality differentiated in morphology-dependent quality traits, constituents, sensory quality, and impurities. MAP-specific descriptors are exemplified and the principles of important determination methods are explained. Most of the general available UPOV and IPGRI descriptors are applicable also for MAP.

An integrated and interdisciplinary research programme with native medicinal plants from tropical forests has been performed in order to obtain new forest products for sustainable use in regional markets vis-à-vis ecosystem conservation. For the success of this programme ethnopharmacological studies are very important with respect to (i) identification of useful plants including medicinal and aromatic species; (ii) recuperation and preservation of traditional knowledge about native plants; and (iii) identification of potential plants with economic value. The plants are selected with a view to evaluate efficacy and safety (pharmacological and toxicological studies), and phytochemical profile and quality control (phytochemical and chromatographic characterization). These studies are very important to add value to plant products and also to mitigate unscrupulous exploitation of medicinal plants by local communities, since multiple use of plants represents an excellent strategy for sustaining the tropical ecosystem through ex situ and in situ conservation. Thus, conservation of tropical resources is possible in conjunction with improvements in the quality of life of the traditional communities and production of new products with therapeutic, cosmetic and ‘cosmeceutic’ value.

Malaria has been treated for over 350 years with quinine and quinine-derived drugs. However, in several areas of the world, some strains of the malarial parasite Plasmodium falciparum have developed resistance against these drugs. Recently, the World Health Organization (WHO) recommended the use of artemisinin-combination treatments (ACT) as the first-line treatment for multidrug-resistant falciparum malaria. The WHO estimates that current supplies of artemisinin are sufficient for only 30 million ACT, and is foreseeing the need for 130–220 million ACT in 2005 (WHO, 2004). Current research on the production of synthetic artemisinin-like compounds by the Roll Back Malaria project, pharmaceutical companies and academia resulted in a promising synthetic artemisinin-like compound (OZ277) which is currently undergoing phase I clinical trials. In about 5 years this drug is expected to be approved and made available to the public, however, meeting current global demands for ACT depends on the immediate availability of affordable artemisinin-derived drugs. This will involve expansion of the area under cultivation of Artemisia annua and improved methods of cultivation and processing of raw material, associated with more efficient methods for extraction and purification of artemisinin from plant material. This review addresses the agricultural, environmental and genetic aspects that may be useful in the successful large-scale cultivation of A. annua and for producing the antimalarial artemisinin in areas where it is urgently needed today. It also includes geographic aspects (latitude and altitude), which will help make decisions about crop establishment in tropical countries, and includes a list of Good Agricultural and Collection Practices for A. annua.